Nissan Motor Company Limited

Ken Nakamura

Yasuo Nakajima

Tadashi Nagai

Junichi Yokoyama

Kunihiko Sugihara

Hiromichi Ofuji

Atsushi Yonezawa

Masanori Takami

Yutaka Matayoshi

Giichi Shioyama

Mitsumasa Inoue

Kizuku Otsubo

Eiichi Ohnishi

Shizuo Ishizawa

Eiji Murata

Syunich Aoyama

In a variable venturi carburetor in which the metering jet portion of fuel changes automatically according to the amount of intake air required to keep the mixture at a constant air-to-fuel ratio at all times, two series-arranged nozzles and an auxiliary fuel passage communicating with the downstream side of the venturi and with the space formed between the two nozzles additionally formed at the fixed venturi portion in such a way that the auxiliary fuel passage can be opened or closed according to engine operating conditions. Therefore, when the auxiliary fuel passage is opened, since fuel is introduced into the venturi through only a single nozzle, a rich mixture is obtained; when the auxiliary fuel passage is closed, since fuel is introduced through two nozzles, a lean mixture is obtained.

Variable venturi carburetor

An intake system of an internal combustion engine including a power cylinder having an intake valve and a fuel injection nozzle, comprising: a throttle chamber upstream open to the atmosphere; primary and secondary throttle valves provided in parallel with each other in the throttle chamber; primary and secondary air passageways leading from the throttle chamber past the primary and secondary throttle valves, respectively, and conjoined together upstream of the intake valve, the secondary passageway being larger in cross sectional area than the primary air passageway and having a reservoir chamber portion larger in cross sectional area than the remaining portion of the secondary passageway; and air heating means provided in the primary air intake pipe and operative to preheat the air to be passed through the primary air intake pipe.

Intake system of internal combustion engine

A spark-ignition internal combustion engine having a combustion chamber, comprises intake and exhaust valves disposed on a cylinder head wall surface and positioned generally symmetrical with each other with respect to the center axis of the bore of an engine cylinder, at least first and second squish areas which are located respectively in first and second sections of the combustion chamber which sections are defined by dividing the combustion chamber into two by a first vertical plane containing the centers of the intake and exhaust valves, and a spark plug whose tip section is disposed on the cylinder head wall surface and positioned in said first section of the combustion chamber thereby enabling use of high compression ratio without causing engine knock.

Spark-ignition internal combustion engine

An electronic controlled carburetor has an induction passage into which fuel is fed by a fuel metering system communicated with the atmosphere through main and auxiliary air bleed passages. The main and auxiliary air bleed passages have therein main and auxiliary solenoid valves, respectively, for altering the rate of air flow therethrough. A control circuit determines the duty ratio of a first pulse signal applied to the main solenoid valve in response to an air/fuel ratio indicative signal from an oxygen sensor. The control circuit determines the duty ratio of a second pulse signal applied to the auxiliary solenoid valve from the duty ratio of the first pulse signal so as to permit the main solenoid valve to operate around 50% duty ratio over all engine operating modes.

Electronic controlled carburetor

In an air-fuel mixture supply device for an internal combustion engine, a butterfly-type throttle valve is disclosed whose upstream face is formed with a raised portion extending around the major of its periphery, but which is broken at least at the middle of the downstream part of the periphery of this upstream face. Thereby distribution of the air-fuel mixture is improved between the cylinders of a multi-cylinder engine.

Butterfly throttle valve with a raised upper lip

An exhaust gas purifying system for an internal combustion engine including at least one combustion chamber connected to an intake port through an intake valve. The system comprises a first passage for passing a portion of exhaust gases discharged from the combustion chamber, a second passage for passing air, a fluid passage, at least one fluid injection nozzle having its one end connected to the fluid passage and the other end extending into the intake port toward the combustion chamber, the fluid injection nozzle adapted to open when the intake valve opens, and means responsive to engine operating condition for connecting the fluid passage to the first passage to permit injection of exhaust gases through the fluid injection nozzle into the combustion chamber during acceleration and for connecting the fluid passage to the second passage to permit injection of air through the fluid injection nozzle into the combustion chamber during normal operation or idling.

Internal combustion engine with an exhaust gas purifying system

An engine system of the invention comprises an internal combustion engine; a carburetor; an exhaust gas recirculation system; an exhaust gas treatment device; and a source of secondary air, in which there is provided a fluid network which interconnects the source of secondary air, the engine exhaust system at a position upstream of the exhaust gas treatment device and the exhaust gas recirculation system at a position upstream of an exhaust gas recirculation valve and there is also provided an air injection control valve fluidly disposed in the fluid network intermediate the source of secondary air and the exhaust gas recirculation system. The air injection control valve is adapted to selectively permit and prevent the admission of air to the exhaust gas recirculation system. A controller for the air injection control valve is also disclosed which comprises a detector that generates as an output signal a first signal responsive to urban driving conditions which are empirically determined to occur when the motor vehicle is driven in urban areas and a second signal responsive to rural driving conditions which are empirically determined to occur when the motor vehicle is driven in rural areas. The controller causes the air injection valve to permit the admission of air to the EGR system when the detector detects the rural driving conditions.

Engine system for motor vehicle

An EGR control system includes a plurality of ON-OFF air valves to control the amount of air admitted into a control passage extending from a source of constant vacuum to a control vacuum chamber upon which an EGR control valve is operated. The air valves are selectively energized by a controller containing a microcomputer wherein an exhaust gas control strategy is stored.

EGR Control system

Engine suction is applied for controlling admission of atmospheric air into a vacuum chamber of an EGR control valve so as to reduce the degree of opening of the EGR control valve during low load running of the engine, and concurrently the vacuum in a venturi of a carburetor is applied for controlling the admission of atmospheric air into the vacuum chamber so as to increase the degree of opening of the EGR control valve during high load running of the engine.

Growing community of inventors

Kawasaki, Japan

Ken Nakamura